One mechanism possibly leading to olfactory dysfunction is a reduction in the nasal airflow accessing the region which houses the olfactory mucosa. Obviously, if nasal airflow is compromised sufficiently, odorant molecules cannot reach the olfactory region and there can be no olfactory perception. Central to the establishment of airflow through the nose is the anatomical configuration of the nasal fossa. Thus, in order to investigate the normal vehicle by which odorant molecules access the region of the olfactory mucosa, we propose to describe the relationship between nasal anatomy and the pattern of nasal airflow in human cadavers. To this end, we will adapt for our purposes the techniques presently used to describe nasal airflow through an anatomically correct model of the human nasal cavity. In addition, we propose to investigate, by anatomical documentation, which nasal airway deformities and obstructions are associated with olfactory deficits. One approach to examining this question is to evaluate the relationship between the changes in nasal patency associated with the "nasal cycle" and olfactory ability. The nasal cycle is a normal physiological phenomenon which results from a cyclic change in the nasal side of greater resistance due to alternate turbinate engorgement that occurs with the periodicity of approximately 2-3 hours. Similarly, in patients with upper respiratory infections we will evaluate the extent to which the obstruction associated with this condition effects olfactory ability. CT scans have proven to be the most powerful tool for evaluating the anatomical status of the nasal cavity. Thus, we propose to evaluate the relationship between olfactory ability and nine anatomic measurements of nasal patency obtained from CT scans. Clinical interventions such as nasal surgery and general anesthesia have been reported in the literature to effect olfactory ability. Thus, we propose to conduct separate prospective studies on each of these two clinical interventions. With each subject serving as his/her own control, the olfactory performance pre-operatively will be compared to that post-operatively. It is projected that out of these studies information will be obtained which will improve the clinical diagnosis and management of patients presenting with complaints of olfactory dysfunction.